CNC Mill Mark Removal in Intake Port

dusterbing the peace said
Wow, you work fast!!!

Interesting to see first pass with a really rough grit; essentially the same as the “washboard” (that term fits perfectly) finish.

Is the test with the valve job as shipped from SM?

Many, many, thanks for doing this!!!

Valve job is factory. My disappointment with this head is the large volume (199cc) and the large throat (93% on a 45 degree seat). The throat was the shocker. I think it's losing a lot of flow throughout the range because of that.